Prosthetic knee joint



FIG. 1 is a front elevational view of a prosthetic knee joint embodying my design.

FIG. 2 is a side elevational view thereof.

FIG. 3 is a rear elevational view thereof.

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a prosthetic knee joint, as shown. 